2 * Copyright (C) 2019 Andreas Baierl
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
25 #include "nir_builder.h"
27 /* Lower gl_FragCoord and transform the w component
28 * according to the following pseudocode:
30 * gl_FragCoord.xyz = gl_FragCoord_orig.xyz
31 * gl_FragCoord.w = 1.0 / gl_FragCoord_orig.w
36 lower_fragcoord_wtrans_filter(const nir_instr
*instr
, UNUSED
const void *_options
)
38 if (instr
->type
!= nir_instr_type_intrinsic
)
41 nir_intrinsic_instr
*intr
= nir_instr_as_intrinsic(instr
);
42 if (intr
->intrinsic
== nir_intrinsic_load_frag_coord
)
45 if (intr
->intrinsic
!= nir_intrinsic_load_deref
)
48 nir_variable
*var
= nir_intrinsic_get_var(intr
, 0);
49 return var
->data
.location
== VARYING_SLOT_POS
;
53 lower_fragcoord_wtrans_impl(nir_builder
*b
, nir_instr
*instr
,
54 UNUSED
void *_options
)
56 nir_intrinsic_instr
*intr
= nir_instr_as_intrinsic(instr
);
59 nir_channel(b
, &intr
->dest
.ssa
, 0),
60 nir_channel(b
, &intr
->dest
.ssa
, 1),
61 nir_channel(b
, &intr
->dest
.ssa
, 2),
62 nir_frcp(b
, nir_channel(b
, &intr
->dest
.ssa
, 3)));
66 nir_lower_fragcoord_wtrans(nir_shader
*shader
)
68 assert(shader
->info
.stage
== MESA_SHADER_FRAGMENT
);
70 return nir_shader_lower_instructions(shader
,
71 lower_fragcoord_wtrans_filter
,
72 lower_fragcoord_wtrans_impl
,